1. Field of the Invention
The present invention relates to a clamp mechanism and a related printer, and more particularly, to a clamp mechanism and a related printer that do not hurt the printing medium.
2. Description of the Prior Art
Please refer to FIG. 1. FIG. 1 is a diagram of a conveying mechanism 10 in the prior art. The conveying mechanism 10 includes a print head 12, a platen roller 14, a pinch roll 16 and a capstan roller 18. The printing medium moves from the print head 12 and the platen roller 14 to the pinch roll 16 and the capstan roller 18. The print head 12 presses the platen roller 14, which means the platen roller 14 clamps the printing medium with the print head 12. The pinch roller 16 is rotated by a driving motor, and conveys the printing medium according to structure of the capstan roller 18, so that predetermined dye on a ribbon can be transferred to the printing medium for forming the pattern by the print head 12. A plurality of thorns 181 is disposed on a surface of the capstan roller 18. The thorns 181 fix the printing medium to prevent separation. A plurality of apertures is formed on the printing medium by the thorns 181 along a conveying path of the printing medium. A conventional printer utilizes Matt technology to conceal the apertures on the printing medium, or obscures the pattern over the apertures directly. However, drawbacks of the apertures are detected by eyes and hand touch easily, so the conventional printer can not utilized to print the high quality pattern. Thus design of a printer with preferable printing quality is an important issue in the mechanical industry.